demoii12_3.cpp

3D游戏编程大师技巧第十二章的源代码

// help menu
if (keyboard_state[DIK_H])
   {
   // toggle help menu 
   help_mode = -help_mode;
   Wait_Clock(100); // wait, so keyboard doesn't bounce
   } // end if

// z-sorting
if (keyboard_state[DIK_S])
   {
   // toggle z sorting
   zsort_mode = -zsort_mode;
   Wait_Clock(100); // wait, so keyboard doesn't bounce
   } // end if

// forward/backward
if (keyboard_state[DIK_UP])
   {
   // move forward
   if ( (cam_speed+=1) > MAX_SPEED) cam_speed = MAX_SPEED;
   } // end if
else
if (keyboard_state[DIK_DOWN])
   {
   // move backward
   if ((cam_speed-=1) < -MAX_SPEED) cam_speed = -MAX_SPEED;
   } // end if

// rotate
if (keyboard_state[DIK_RIGHT])
   {
   cam.dir.y+=3;
   
   // add a little turn to object
   if ((turning+=2) > 25)
      turning=25;
   } // end if

if (keyboard_state[DIK_LEFT])
   {
   cam.dir.y-=3;

   // add a little turn to object
   if ((turning-=2) < -25)
      turning=-25;

   } // end if
else // center heading again
   {
   if (turning > 0)
       turning-=1;
   else
   if (turning < 0)
       turning+=1;

   } // end else



// decelerate camera
if (cam_speed > (CAM_DECEL) ) cam_speed-=CAM_DECEL;
else
if (cam_speed < (-CAM_DECEL) ) cam_speed+=CAM_DECEL;
else
   cam_speed = 0;

// move camera
cam.pos.x += cam_speed*Fast_Sin(cam.dir.y);
cam.pos.z += cam_speed*Fast_Cos(cam.dir.y);

// move point light source in ellipse around game world
lights2[POINT_LIGHT_INDEX].pos.x = 1000*Fast_Cos(plight_ang);
lights2[POINT_LIGHT_INDEX].pos.y = 100;
lights2[POINT_LIGHT_INDEX].pos.z = 1000*Fast_Sin(plight_ang);

if ((plight_ang+=3) > 360)
    plight_ang = 0;

// move spot light source in ellipse around game world
lights2[SPOT_LIGHT2_INDEX].pos.x = 1000*Fast_Cos(slight_ang);
lights2[SPOT_LIGHT2_INDEX].pos.y = 200;
lights2[SPOT_LIGHT2_INDEX].pos.z = 1000*Fast_Sin(slight_ang);

if ((slight_ang-=5) < 0)
    slight_ang = 360;

// generate camera matrix
Build_CAM4DV1_Matrix_Euler(&cam, CAM_ROT_SEQ_ZYX);

////////////////////////////////////////////////////////
// insert the scenery into universe
for (index = 0; index < NUM_SCENE_OBJECTS; index++)
    {
    // select proper object first
    obj_work = &obj_array[(int)scene_objects[index].w];

    // reset the object (this only matters for backface and object removal)
    Reset_OBJECT4DV2(obj_work);

    // set position of tower
    obj_work->world_pos.x = scene_objects[index].x;
    obj_work->world_pos.y = scene_objects[index].y;
    obj_work->world_pos.z = scene_objects[index].z;

    // move objects
    scene_objects[index].x+=scene_objects_vel[index].x;
    scene_objects[index].y+=scene_objects_vel[index].y;
    scene_objects[index].z+=scene_objects_vel[index].z;

    // test for out of bounds
    if (scene_objects[index].x >= UNIVERSE_RADIUS || scene_objects[index].x <= -UNIVERSE_RADIUS)
       { 
       scene_objects_vel[index].x=-scene_objects_vel[index].x;
       scene_objects[index].x+=scene_objects_vel[index].x;
       } // end if

    if (scene_objects[index].y >= (UNIVERSE_RADIUS/2) || scene_objects[index].y <= -(UNIVERSE_RADIUS/2))
       { 
       scene_objects_vel[index].y=-scene_objects_vel[index].y;
       scene_objects[index].y+=scene_objects_vel[index].y;
       } // end if

    if (scene_objects[index].z >= UNIVERSE_RADIUS  || scene_objects[index].z <= -UNIVERSE_RADIUS)
       { 
       scene_objects_vel[index].z=-scene_objects_vel[index].z;
       scene_objects[index].z+=scene_objects_vel[index].z;
       } // end if

    // attempt to cull object   
    if (!Cull_OBJECT4DV2(obj_work, &cam, CULL_OBJECT_XYZ_PLANES))
       {
       MAT_IDENTITY_4X4(&mrot);
 
       // rotate the local coords of the object
       Transform_OBJECT4DV2(obj_work, &mrot, TRANSFORM_LOCAL_TO_TRANS,1);

       // perform world transform
       Model_To_World_OBJECT4DV2(obj_work, TRANSFORM_TRANS_ONLY);

       // insert the object into render list
       Insert_OBJECT4DV2_RENDERLIST4DV2(&rend_list, obj_work,0);

       } // end if
 
    } // end for

// update rotation angles
if ((x_ang+=.2) > 360) x_ang = 0;
if ((y_ang+=.4) > 360) y_ang = 0;
if ((z_ang+=.8) > 360) z_ang = 0;

// reset number of polys rendered
debug_polys_rendered_per_frame = 0;
debug_polys_lit_per_frame = 0;

// remove backfaces
if (backface_mode==1)
   Remove_Backfaces_RENDERLIST4DV2(&rend_list, &cam);

// apply world to camera transform
World_To_Camera_RENDERLIST4DV2(&rend_list, &cam);

// clip the polygons themselves now
Clip_Polys_RENDERLIST4DV2(&rend_list, &cam, ((x_clip_mode == 1) ? CLIP_POLY_X_PLANE : 0) | 
                                            ((y_clip_mode == 1) ? CLIP_POLY_Y_PLANE : 0) | 
                                            ((z_clip_mode == 1) ? CLIP_POLY_Z_PLANE : 0) );

// light scene all at once 
if (lighting_mode==1)
   {
   Transform_LIGHTSV2(lights2, 4, &cam.mcam, TRANSFORM_LOCAL_TO_TRANS);
   Light_RENDERLIST4DV2_World2_16(&rend_list, &cam, lights2, 4);
   } // end if

// sort the polygon list (hurry up!)
if (zsort_mode == 1)
   Sort_RENDERLIST4DV2(&rend_list,  SORT_POLYLIST_AVGZ);

// apply camera to perspective transformation
Camera_To_Perspective_RENDERLIST4DV2(&rend_list, &cam);

// apply screen transform
Perspective_To_Screen_RENDERLIST4DV2(&rend_list, &cam);

// lock the back buffer
DDraw_Lock_Back_Surface();

// reset number of polys rendered
debug_polys_rendered_per_frame = 0;

// render the renderinglist
if (wireframe_mode  == 0)
   Draw_RENDERLIST4DV2_Wire16(&rend_list, back_buffer, back_lpitch);
else
if (wireframe_mode  == 1)
   {
   // initialize zbuffer to 16000 fixed point
   Clear_Zbuffer(&zbuffer, (16000 << FIXP16_SHIFT));


#if 0
RENDERCONTEXTV1 rc;

// no z buffering, polygons will be rendered as are in list
#define RENDER_ATTR_NOBUFFER                     0x00000001  

// use z buffering rasterization
#define RENDER_ATTR_ZBUFFER                      0x00000002  

// use 1/z buffering rasterization
#define RENDER_ATTR_INVZBUFFER                   0x00000004  

// use mipmapping
#define RENDER_ATTR_MIPMAP                       0x00000010  

// enable alpha blending and override
#define RENDER_ATTR_ALPHA                        0x00000020  

// use affine texturing for all polys
#define RENDER_ATTR_TEXTURE_PERSPECTIVE_AFFINE   0x00000100  

// use perfect perspective texturing
#define RENDER_ATTR_TEXTURE_PERSPECTIVE_CORRECT  0x00000200  

// use linear piecewise perspective texturing
#define RENDER_ATTR_TEXTURE_PERSPECTIVE_LINEAR   0x00000400  

// use a hybrid of affine and linear piecewise based on distance
#define RENDER_ATTR_TEXTURE_PERSPECTIVE_HYBRID1  0x00000800  
 
// not implemented yet
#define RENDER_ATTR_TEXTURE_PERSPECTIVE_HYBRID2  0x00001000  

#endif

     // set up rendering context
   rc.attr         = RENDER_ATTR_ZBUFFER  
                     | RENDER_ATTR_ALPHA  
                     //| RENDER_ATTR_MIPMAP  
                     //| RENDER_ATTR_BILERP
                     | RENDER_ATTR_TEXTURE_PERSPECTIVE_AFFINE;
   
   rc.video_buffer   = back_buffer;
   rc.lpitch         = back_lpitch;
   rc.mip_dist       = 3500;
   rc.zbuffer        = (UCHAR *)zbuffer.zbuffer;
   rc.zpitch         = WINDOW_WIDTH*4;
   rc.rend_list      = &rend_list;
   rc.texture_dist   = 0;
   rc.alpha_override = -1;

   // render scene
   Draw_RENDERLIST4DV2_RENDERCONTEXTV1_16(&rc);
   }

// unlock the back buffer
DDraw_Unlock_Back_Surface();

sprintf(work_string,"Lighting [%s]: Ambient=%d, Infinite=%d, Point=%d, Spot=%d, BckFceRM [%s], Zsort [%s]", 
                                                                                 ((lighting_mode == 1) ? "ON" : "OFF"),
                                                                                 lights[AMBIENT_LIGHT_INDEX].state,
                                                                                 lights[INFINITE_LIGHT_INDEX].state, 
                                                                                 lights[POINT_LIGHT_INDEX].state,
                                                                                 lights[SPOT_LIGHT2_INDEX].state,
                                                                                 ((backface_mode == 1) ? "ON" : "OFF"),
                                                                                 ((zsort_mode == 1) ? "ON" : "OFF"));


Draw_Text_GDI(work_string, 0, WINDOW_HEIGHT-34-16, RGB(0,255,0), lpddsback);

// draw instructions
Draw_Text_GDI("Press ESC to exit. Press <H> for Help.", 0, 0, RGB(0,255,0), lpddsback);

// should we display help
int text_y = 16;
if (help_mode==1)
    {
    // draw help menu
    Draw_Text_GDI("<A>..............Toggle ambient light source.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<I>..............Toggle infinite light source.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<P>..............Toggle point light source.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<S>..............Toggle spot light source.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<N>..............Next object.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<W>..............Toggle wire frame/solid mode.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<B>..............Toggle backface removal.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<S>..............Toggle Z sorting.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<H>..............Toggle Help.", 0, text_y+=12, RGB(0,0,0), lpddsback);
    Draw_Text_GDI("<ESC>............Exit demo.", 0, text_y+=12, RGB(0,0,0), lpddsback);

    } // end help

sprintf(work_string,"Polys Rendered: %d, Polys lit: %d", debug_polys_rendered_per_frame, debug_polys_lit_per_frame);
Draw_Text_GDI(work_string, 0, WINDOW_HEIGHT-34-16-16, RGB(0,255,0), lpddsback);

sprintf(work_string,"CAM [%5.2f, %5.2f, %5.2f]",  cam.pos.x, cam.pos.y, cam.pos.z);

Draw_Text_GDI(work_string, 0, WINDOW_HEIGHT-34-16-16-16, RGB(0,255,0), lpddsback);

// flip the surfaces
DDraw_Flip2();

// sync to 30ish fps
Wait_Clock(30);

// check of user is trying to exit
if (KEY_DOWN(VK_ESCAPE) || keyboard_state[DIK_ESCAPE])
    {
    PostMessage(main_window_handle, WM_DESTROY,0,0);
    } // end if

// return success
return(1);
 
} // end Game_Main

//////////////////////////////////////////////////////////